Gateway MA7

Unfortunately im the go to guy to fix all my friends computers, lol.
First there is a problem with the video screen. Since i can barely see that there is writing on the screen when i try to boot i guess it needs that lighting part, forget the name of it, backlight i think. So now its connected to an external monitor and i have video.

However, win xp pro wont install. I reformatted the hard drive using an external docking station, those new usb 3 jobs. Formatted NTFS went fine in computer management, all one drive, no partitions. When i reformatted the hard drive i wasnt able to set the drive as c since my pc was using c so it gave me the letter L.
I set the bios to default settings, then went back into bios to check all the settings, seem to be fine. The bios sees the hard drive, then i went to boot menu and set dvd as first boot and hard drive as second boot. Then i saved the bios changes properly.

But when i try to install win xp pro i get an error message telling me there is no hard drive or that it cant find any hard drive. The hard drive is sata and its plugged in properly, really no way it can be plugged in incorrectly due to the tray it is sitting in so the hd is in right. Its a 120 gig Seagate and the bios even sees all the numbers that are printed on the hard drive. What is wrong?

thanks for your patience and help.